已知当x趋向于0时,∫(x,-x)(sin(t)+sin(t^2))d(t)与a(x^k)是等价无穷小,则 ( )A.a=3,k=3/2 B.a=2/3,k=3C.a=3,k=2/3D.a=3/2,k=3∫(x,-x)(sin(t)+sin(t^2))d(t)中(x,-x)顺序弄反了,应该是(-x,x)
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已知当x趋向于0时,∫(x,-x)(sin(t)+sin(t^2))d(t)与a(x^k)是等价无穷小,则()A.a=3,k=3/2B.a=2/3,k=3C.a=3,k=2/3D.a=3/2,k=3∫
已知当x趋向于0时,∫(x,-x)(sin(t)+sin(t^2))d(t)与a(x^k)是等价无穷小,则 ( )A.a=3,k=3/2 B.a=2/3,k=3C.a=3,k=2/3D.a=3/2,k=3∫(x,-x)(sin(t)+sin(t^2))d(t)中(x,-x)顺序弄反了,应该是(-x,x)
已知当x趋向于0时,∫(x,-x)(sin(t)+sin(t^2))d(t)与a(x^k)是等价无穷小,则 ( )
A.a=3,k=3/2
B.a=2/3,k=3
C.a=3,k=2/3
D.a=3/2,k=3
∫(x,-x)(sin(t)+sin(t^2))d(t)中(x,-x)顺序弄反了,应该是(-x,x)
已知当x趋向于0时,∫(x,-x)(sin(t)+sin(t^2))d(t)与a(x^k)是等价无穷小,则 ( )A.a=3,k=3/2 B.a=2/3,k=3C.a=3,k=2/3D.a=3/2,k=3∫(x,-x)(sin(t)+sin(t^2))d(t)中(x,-x)顺序弄反了,应该是(-x,x)
反不反都不影响解题,再说谁知道你括号里是上限在前还是下限在前啊……
积分里sint是奇函数对称区间积分,为0,直接拿掉.剩sin(t^2)是偶函数,对称区间积分等于2倍的0到x积分.求导后为2sin(x^2)∽2x^2.
a(x^k)求导后为ak(x^(k-1)),比较得ak=2,k-1=2.选B